Your point is well made that it would be nice if Apple listened to customers sufficiently engaged to comment! This particular thing is NOT the end of the world, but there are circumstances where one cannot, or wishes not to, access wifi and that there is no phone signal, or one wishes not to send whatever item by that route.
There has been comment in these forums going back to at least 2009 criticising Apple, with varying degrees of vehemence, for not fully and properly implementing Bluetooth to enable simple and effective file transfer. That,to me, seems to be a pretty persistent customer request for something that is a standard, commonly defined, capability for mobile and other devices. Not least because it isolates Apple users from a capability the dominant phone operating system (and PCs etc) can all use.
That criticism is not unreasonable since all devices going back at least that far contain the technical capability (hw/sw) to do this. Indeed, a number of third party apps have used it, but it would have been even easier for them, and everyone else, if bluetooth transfer had, for example, been made accessible more easily, perhaps via "open in".
Some years back, Apple even removed from the app store, within days of it appearing, a very handy on/off app for Bluetooth, only to put that very capability into iOS7 as an "innovation".
What is it that Apple have against Bluetooth? As another poster commented, it would be nice to get a response to these comments, but one cannot help but end up suspecting that this approach is to do with maintaining Apple's "walled garden" rather than listening to customers.
Today, if you ask an iPhone 4/4s to look for other bluetooth devices, whereas it used to find other iphones, it no longer will under iOS7.
And yet if you run one of the third party apps using Bluetooth (eg Phototransfer) on an iPhone 4 with iOS7 it WILL detect another iPhone and it will "pair", create a profile and transfer data - even if wifi is off.
This implies that iOS7 is deliberately built to mask this capability, except when it is used by Airdrop - and also implies that Airdrop could actually work on older models. After all, Phototransfer can use both wifi and bluetooth for file transfers.
It is disappointing that Apple chooses to do this and, although this is not a big deal it is one of those niggles that points at attitude and inclines me, at least, to consider alternatives next time I change devices.
HINT - a nice response would be for Apple not only to enable Airdrop in older devices, but also, in an act of unusual openness, use all their outstanding design and technical skills to make it so that it can work with non-apple devices too!